The present invention relates to an electromagnet, particularly for actuating valves, with a sheath-like magnet housing. The housing encompasses a pole core on the actuation side of the electromagnet. An actuation member is accessible on the electromagnet and is movable by means of the armature of the magnet. The magnet housing is connected with the pole core in an area adjacent to the actuating side by means of a connection which is tightly fitting at least in that area.
An electromagnet for actuating valves is disclosed in DE 195 04 185 A1. For this electromagnet to satisfy requirements for higher structural resistance and problem-free sealing of the magnet housing from the exterior environment, which sealing is particularly important during its use for the actuation of hydraulic valves, a costly structure with considerable manufacturing outlay generally results for conventional valves.
Objects of the present invention are to provide an electromagnet for actuating valves which is relatively simple and inexpensive to manufacture, particularly in view of its especially beneficial sealing and resistance properties.
The objects of the present invention are attained by an electromagnet having a connection between its magnet housing and pole core incorporating an annular groove formed between magnet housing and pole core in the periphery of the pole core. A removable sealing element is fitted in that groove. Another annular groove in the magnet housing also engages the sealing element. The connection forms contacts surfaces by engaging tightly and fitting on the interior walls of the pole core annular groove, as well as a contacting sealing surface encompassing the sealing element.
By virtue of this construction, with tightly fitting application of the frictional connection between the magnet housing and pole core, a problem-free sealing by contact of the annular groove of the magnet housing on the sealing element located in the adjacent annular groove is obtained simultaneously. As opposed to conventional electromagnets, wherein grooves forming inwardly aligned openings are uniformly distributed around the periphery of the magnet housing to form the connection, the connection obtained according to the present invention is without penetrating openings passing all the way through for a pressure-sealed sealing off of the housing.
The sealing element can be an O-ring, a gap seal or a suitable coating of the interior of the annular groove and/or of the pole housing in the area of the annular groove.
The manufacture is especially simple and low-cost when the magnet housing is a one-piece extrusion-molded part. That part includes an inwardly aligned open pole tube on its bottom, opposite the actuating end, open to the exterior of the magnet housing. The magnet housing is also the reverse side of the pole body.
Other objects, advantages and salient features of the present invention will become apparent from the following detailed description, which, taken in conjunction with the annexed drawing, discloses a preferred embodiment of the present invention.